The 'Mr. Blue Sky' meme centers around the iconic 1977 song by Electric Light Orchestra (ELO). While it has existed in various forms, it gained massive internet fame through its use in the opening credits of Guardians of the Galaxy Vol. 2, featuring Baby Groot dancing through a chaotic battle. In meme culture, the song is frequently used as a background track for fast-paced video montages, often contrasting the upbeat, cheery melody with footage of intense action, epic fails, or historical events. It represents a feeling of pure, unadulterated joy or irony, depending on whether the visuals match the optimistic lyrics about the return of the sun.